Crate merino_integration_tests

Expand description

Tests for Merino that work by reading from the external API only.

Since the URL endpoints Merino exposes to the world are its public API, and other systems depend on them, the paths used in tests here are important details, and used to keep compatibility.

This is structured as a separate crate so that it produces a single test binary instead of one test per file like would happen if this were merino/tests/.... This improves compilation and test times.

The primary tool used by tests is merino_test, which creates mock servers, sets up the application for testing, and provides helpers to inspect the state of the app. It then calls the test function that is passed to it, providing the above tools as an argument.

Examples:

A realistic test:

use merino_integration_tests::{TestingTools, merino_test_macro};

#[merino_test_macro(|settings| settings.debug = true)]
async fn lbheartbeat_works(TestingTools { test_client, .. }: TestingTools) {
   let response = test_client
       .get("/__lbheartbeat__")
       .send()
       .await
       .expect("failed to execute request");

   assert_eq!(response.status(), StatusCode::OK);
   assert_eq!(response.content_length(), Some(0));
}

Basic usage:

use merino_integration_tests::{merino_test_macro, TestingTools};

#[merino_test_macro]
async fn test_function(TestingTools { test_client, .. }: TestingTools) {
    // test using test_client
}

Settings can be customized:

use merino_integration_tests::{merino_test_macro, TestingTools};

#[merino_test_macro(|settings| settings.debug = true)]
async fn test_function(TestingTools { test_client, .. }: TestingTools) {
    // test using test_client while the debug setting is true.
}

Other test macros, like parameterized, can be used:

use merino_integration_tests::{TestingTools, merino_test_macro};
use parameterized::parameterized;

#[merino_test_macro(|settings, ttl: u64| settings.redis_cache.default_ttl = ttl)]
#[parameterized(ttl = { 300, 600 })]
async fn test(TestingTools { .. }: TestingTools) {
    // test will run twice, once with each TTL setting.
}